1. Field of the Invention
The invention relates to a waterproofing seal for use with an electrical connector.
2. Description of the Related Art
An electrical connector assembly includes first and second connectors that are configured to mate with one another. Each connector typically has a housing and at least one cavity extends through the housing. Each cavity is configured to receive a terminal fitting. One end of each terminal fitting typically is connected to a conductor, such as the wire, cable, busbar, an electrical device or a conductive region of a circuit board. The opposed end of each terminal fitting is configured for achieving electrical connection with a terminal fitting in the mating connector.
Many connectors, such as those used in automotive vehicles, will be exposed at least periodically to moisture. The housing of an electrical connector typically is formed from a resin or other material that can withstand periodic exposure to moisture. However, moisture can adversely affect the metallic terminal fittings and can cause a shorting between two terminal fittings. A short circuit can have serious effects on critical components of a vehicle, such as warning lights, airbags and the like.
Many connectors include an elastomeric seal to prevent intrusion of moisture into the region of the connector that contains the terminal fittings and the conductors to which the terminal fittings are connected. A seal of this type typically is mounted at an area where two parts of the mating housings will telescope together. For example, a frame-shaped seal or a toroid-shaped seal may be mounted over one housing of a connector assembly. The end of the mating housing will abut against the seal when the housings are connected. Thus, the seal engages the interface between the two housings to provide sealing.
An electrical connector typically is assembled at one location and then transported to another location for connection with a mating connector. For example, an electrical connector may be mounted to an end of a wiring harness assembled at a manufacturing facility of an electrical component supplier. The wiring harness then may be shipped to an automobile manufacturer for connection with electrical equipment that is assembled into the vehicle. The seals in such connectors must be mounted in a way that will prevent separation during transit.
Connectors must be designed to accommodate periodic disconnection for maintenance, repair or replacement. Forces generated during such disconnection can urge a seal in a direction to displace the seal from its properly mounted position. The seal might be mounted improperly when the connectors are reconnected to one another.
In view of the above, the seal of an electrical connector must be mounted in a way that will prevent separation during transit and that will prevent movement during a disconnection of a connector assembly.
The housing of an electrical connector generally is formed from a rigid material such as a synthetic resin. The seal, on the other hand, generally is formed from an elastomeric material, such as rubber. The elastomeric frame-shaped seal may be expanded slightly to telescope over one of the housings to be sealed. Connectors continue to be made smaller in response to the demands of purchasers of such connectors. As a result, the frame-shaped elastomeric seals generally are small and must be assembled to a small housing. The small sizes of electrical connectors complicate the assembly of the seal to the housing.
Prior art electrical connectors have used three different approaches for retaining a seal on the housing. The first approach relies merely on the friction between the expanded elastomeric material of the seal and the rigid resin of the housing. However, the seal can be disengaged or repositioned during transit or during a disconnection of two housings, thereby creating the potential for improper sealing during a connection or reconnection.
The second approach employs a separate cover formed from a rigid material and mounted to the housing after the seal has been positioned. The rigid cover can be locked mechanically to the housing and ensures that the seal remains in place during transit. The separate cover works very well for assuring the position of the seal. However, the cover adds to the dimensions of the connector and hence impedes efforts to reduce the size of a connector. Additionally, the separate cover imposes a cost penalty in terms of material costs, inventory control and assembly costs. In this regard, the electrical connector industry is highly competitive and even small cost savings can be commercially very advantageous.
The third approach employs an elastomeric seal with projections. The housing then is formed with apertures for receiving the projections. The seal is manipulated so that the projections on the seal engage in the apertures on the housing to hold the seal in place. A properly mounted seal of this type also works well. However, prior art connectors of this type have entailed complicated assembly, particularly in view of the decreasing sizes of the connectors. In particular, the projections on the known elastomeric seal have been difficult to mount properly in the openings on the housing. Accordingly, assembly often has required the use of a screwdriver-like tool. The tool can damage the housing in a way that could lead to the intrusion of the water that is intended to be avoided by the seal. In other instances, the tool can separate plastic debris from the housing. The debris can remain in the housing and can affect the performance of the connector.
In view of the above, it is an object of the subject invention to provide a seal that can be mounted efficiently to a housing of a connector.
Another object of the invention is to provide a seal that can be mounted without the use of a mounting tool.